Method and apparatus enabling multi threaded program execution for a Cobol program including OpenMP directives by utilizing a two-stage compilation process

ABSTRACT

A method and apparatus is disclosed for compilation of an original Cobol program with support for improved performance by increased parallelism during execution using multiple threads of processing. The approach includes a two stage compilation process, the first compilation/translation step by a first specialized compiler/translator that takes as input a Cobol source program that includes parallelization directives, and produces as output an intermediate computer program in a second computer programming language, the intermediate program including parallelization directives in the second computer programming language. The intermediate program is then compiled utilizing a selected second compiler that provides support for parallelism described in the second programming language. The approach optionally allows for use of pragmas serving as parallelization directives to the compiler in the original Cobol program or in the intermediate program.

CROSS REFERENCE TO RELATED APPLICATIONS

Continuation of U.S. patent application Ser. No. 12/589,304 filed onOct. 20, 2009

Reference U.S. Provisional Application No. 61/459,227 filed Dec. 9, 2010

Reference U.S. Application No. 61/459,227 filed Dec. 7, 2011

This Patent Application claims priority to and is a continuation of U.S.patent application Ser. No. 12/589,304 filed on Oct. 20, 2009, thedisclosure of which is hereby incorporated herein by reference in fulland in its entirety as part of this specification. All other referencedpatents and applications are also incorporated herein by reference intheir entirety. Furthermore, where a definition or use of a term in areference, which is incorporated by reference herein, is inconsistent orcontrary to the definition of that term provided herein, the definitionof that term provided herein shall govern the meaning of such term.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

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INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC

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BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is related to the fields of computing machines; parallelprocessing; parallel computing; multiple thread program execution; thecomputer language Cobol; the computer languages JAVA, C/C++ and Fortran;computer program compilers; computer languages, and other closelyrelated computer art.

2. Description of the Related Art

In the field of computing machines and computing performance, computerusers have become accustomed to computer performance increasing steadilyover the years as a result of technological innovation in the hardwareof computers. However, there are limits on technology which tend tolimit continued increases in computer hardware performance. For example,certain technical limitations tend to limit how fast a computer programcan run on a single computer.

An alternative to increasing performance of a program on a single orsmall number of processing units is to spread the work to be done acrossmultiple processors or multiple computers. Innovation and technicaladvancement in this area have provided for increasing computer programperformance by developing techniques for spreading work across aplurality of computers or central processing units. A common term forthis spreading of work is “parallelization”. There are many forms ofparallelization and ways of achieving parallelization which arediscussed at length in literature surrounding the art and which will notbe discussed here. One particular area of research and significantdevelopment which is of particular interest in the field ofparallelization is a standard for describing and enablingparallelization called OpenMP Architecture (Open Multi-ProcessingArchitecture). “OpenMP” is a trademark of the OpenMP Architecture ReviewBoard, and the standard is described on the Internet at awebsite“OpenMP.org” The OpenMP Architecture is described within thiswebpage as “API Specification for Parallel Programming”. Wikipedia.orgfurther describes OpenMP as:

-   -   “The OpenMP (Open Multi-Processing) is an application        programming interface (API) that supports multi platform shared        memory multiprocessing programming in C, C++ and Fortran on many        architectures, including Unix and Microsoft Windows platforms.        It consists of a set of compiler directives, library routines,        and environment variables that influence run-time behavior.    -   Jointly defined by a group of major computer hardware and        software vendors, OpenMP is a portable, scalable model that        gives programmers a simple and flexible interface for developing        parallel applications for platforms ranging from the desktop to        the supercomputer.    -   An application built with the hybrid model of parallel        programming can run on a computer cluster using both OpenMP and        Message Passing Interface (MPI), or more transparently through        the use of OpenMP extensions for non-shared memory systems.”

OpenMP as a project was initiated in 1997 at a major conference on HighPerformance Computing Networking, and Storage held in San Jose, Calif.The conference was named “Supercomputing 1997”. The proposal for aparallel programming “standard” grew out of a “birds of a feather”session to unveil new portable programming interfaces for shared memoryparallel computers. Following the conference a company was set up to ownand maintain the new informal standard and it was called the OpenMPArchitectural Review Board (ARB).

The OpenMP architecture provides a methodology and programming languageenhancements that enable processing with parallel threads of processing.OpenMP requires support within (or “by”) a compiler, that is, it is notjust a library that is called; it requires support by the compileritself. OpenMP today is supported by several major compilers (GNU Ccompiler, Intel, Microsoft) for computer programs written in thelanguages of C/C++, and Fortran. There are books and classes on parallelprogramming based upon OpenMP.

However, OpenMP architectural support for programs written in othercomputer languages such as Cobol, Pascal and other either “older” orless common computer programming languages is not provided by majorcomputer program compiler manufacturers such as Intel, Microsoft, or byproviders of open source compilers such as GNU.org. As a result, thebenefits of programming utilizing OpenMP to achieve parallelism are notcurrently available for programs written in these older languages, andsupport is not likely to be provided in the future by major compilermanufacturers because most new program development is done in moremodern languages.

However, Cobol is still the programming language for many large computerbusiness applications that are in production use today, and theperformance of these programs or applications is often critical tooperation of a business. Therefore, it would be beneficial if theselarge computer applications could be made to benefit from parallelprogramming in order to improve their performance during execution.Improvement in performance of what are commonly called “batch” programsmight be especially important. The term “Batch” is used to describe ajob, often run at night, that typically processes a large amount of datafrom a day of recorded transactions. Oftentimes “batch” programs are runat night and oftentimes must be completed before more transaction datacan be accumulated (the next day for example).

Providing support for parallelization techniques by a compiler for alanguage such as Cobol is a very significant task for several reasons.First of all, developing a new compiler or significantly enhancing anexisting compiler for any purpose can be a large task. Second, providingfor parallelization enabling concepts within generated code from acompiler is a difficult job, and would be a very significant developmenttask. Third, one major component of “good” compilers is providing afacility/mechanism/capability for carrying out very extensiveoptimization of generated code in order to achieve good performanceduring execution, and support for OpenMP would typically have impact onthose optimizations. For these reasons and others such as lack oflimited resources, innovation, financial burdens etc., major compilerbuilders have not provided a Cobol compiler that supports parallelismsuch as the OpenMP architecture.

Because of the business nature of most Cobol applications, existingCobol compilers used by large businesses are very carefully maintainedby vendors in providing for backwards compatibility and to avoid anypossible introduction of bugs or flaws in the code generation process.The importance of producing correct calculations is emphasized and thus,even the smallest changes are typically verified carefully by runninglarge numbers of test programs. As a result, changes and improvements toCobol compilers are made slowly and carefully, possibly evenreluctantly.

Another reason parallelization support has not been provided for theCobol programming language is that the language of Cobol is notnecessarily well suited to parallelization. The Cobol language, becauseit is quite “old”, has typically been used to describe a program thatexists statically in memory with static memory variables, and oftentimeswithout the use of “modern” programming constructs such as “stacks” orautomatic memory allocation and de-allocation. This tends to createconflicts in the use of memory based variables when attempts are made toparallelize program execution, because parallelization typicallyrequires at least some degree of isolation of memory between the unitsof parallelized code. Also, there are no OpenMP library facilitiesavailable which directly provide OpenMP support for the Cobol language.

But, improving the performance of programs written in Cobol ispotentially important, and improving performance by providing forsupport of parallel processing in the execution of a Cobol program wouldresult in a potentially significant increase in performance by enablingapplication and utilization of multiple processors or computing cores toa single program or problem which was normally run, in the prior art, asa single-thread process or procedure. The same is also true for otherlanguages such as Pascal, PL/1, or other possibly “older” languageswhere no support for parallelism is currently provided by major compilerproviders.

The state of the art has also evolved such that parallelization ormultithreading of programs now has some increased potential for beingautomated, or at least done with more help by tools than in the past.One company that is exploring this area of research is a Swedish companycalled Nema Labs which is developing a tool called “FasThread”. NemaLabs has a website at: “NemaLabs.com”. From the company's website is thestatement: “Nema Labs is a privately held company founded in 2006 withthe mission to provide programmers with powerful and easy-to-usethreading tools for multi-core platforms. The technology base originateson world-class research . . . ”

Nema Labs provides a tool which attempts to semi-automate theparallelization of programs written in “C” and is currently working on aversion of the tool which also supports “C++”. The FasThread's analysisand processing tool includes a mechanism for inserting OpenMP pragmasinto programs in the “C” language based upon analysis by the tool. Thistype of tool provides the potential of being useful in achievingparallelization. It utilizes OpenMP and is not applicable to a sourceprogram described in any language except its “native” input language ofC.

A Cobol programmer may thus now be motivated to look at the potentialfor parallelization of certain, possibly large, Cobol programs, in spiteof the possibility that parallelization of these programs may not havebeen feasible in the past.

BRIEF SUMMARY OF THE INVENTION

It would therefore be an advantage to provide a method and/or apparatusfor compilation of a program written in a source computer language notnormally supported for OpenMP, which enables parallelization duringexecution of the generated code (either object or executable). It isalso an advantage to provide a method of compilation designed toeliminate need for development of a Cobol compiler with integratedparallelization support, and with the method further providing forminimal maintenance effort in the support of providing such a methodand/or apparatus.

An illustrated embodiment of the present invention provides support fora method and apparatus for carrying out compilation of an original Cobolprogram which produces an executable program that supports multiplethreads of processing, improving performance of the original Cobolprogram during execution.

The method according to an illustrated embodiment implements a two-stepor two-phase approach in performing a compilation of an original Cobolprogram. In the illustrated embodiment, a first compiler or translatoris utilized in a first phase of the two phase approach to analyze,process, and translate the original Cobol program source into anintermediate source form in a second computer programming language. Thisintermediate source produced in the first phase is in a form fordescribing a program in a manner suited for parallelization through theuse of parallelization directives such as the type used by the OpenMParchitecture. In a subsequent second phase of the two phase approach, asecond selected compiler, which provides support for the parallelizationof an input program described in that second computer language, isutilized to compile the intermediate source and produce as an output, amultithread executable program for running on multiple processors orcomputing cores.

More specifically, as described with reference to the illustratedembodiment, a first compiler translates in a special way a Cobol sourceprogram into an intermediate program. A second selected compiler readsthe intermediate program and produces, as an output file or files, anexecutable program having functionality described by the original Cobolsource, and which further includes code containing directives thatenables parallelism within at least some regions of processing when theresulting executable program is run or executed. The second compiler mayalso as an alternative produce an object file which is used, typicallywith other object files, in producing an executable program. In oneillustrated embodiment, the first compiler translates in a special way aCobol program into an intermediate program in the “C” programminglanguage. A second compiler reads as input the intermediate “C” programand builds an executable (object file or executable program file) withparallelization enabled (processing by multiple threads). (Executableprogram being meant to describe in general terms any sort of file thatmay be used in processing. Examples of this type of file are an actualexecutable file, or an object file that can be used to produce anexecutable file, or a DLL (Dynamic Link Library) file, or any file whichat run-time can be loaded or processed and loaded into memory forexecution).

In this manner, an executable (or executable program) is produced basedupon the input Cobol program, the executable program providingparallelism by utilizing multiple threads of processing duringexecution. Because of multi-threaded execution or processing, theexecutable program is typically capable of running observably fasterthan a program run with no parallelism (single thread). That is, therate of observable work completed in a given time will typically beimproved (i.e. be made greater) when the executable program is processedby multiple processing threads, in comparison to a standard approach inwhich the executable program (or at least the main part of theexecutable program) is processed by only one thread. In some cases, therate of work being completed can be seen to increase at a rate relatedalmost directly proportional to the number of threads used.

The compilation, analysis and translation by a compiler in the firststage of the illustrated embodiment is a specialized translationresulting in an output in a specific syntax, style and having anordering of output statements and declarations supportive ofparallelization. The compiler in the first stage or first phase analyzesthe original Cobol program and produces as output, a translated orintermediate program (typically in C/C++ of Fortran) which isspecifically organized so as to enable the building of an executableprogram which provides for parallelism using multiple threads, and whoseorganization is the same or similar to the organization typicallyrequired by a parallelization standard such as OpenMP. That is, thestyle (constructs chosen for use in the translation) and syntax of thetranslated output from the first compiler is dependent on the specificparallelization desired and the style necessary in order for theintermediate program to be processed by a second, parallel capablecompiler of the illustrated embodiment.

As discussed, the compiler of the first stage produces an intermediateprogram in a second computer program language, that intermediate programis translated in a manner organized to accommodate and include withinthe intermediate program parallelization directives that are in formsuitable to be processed in a second stage of compilation by a selectedsecond compiler; the second compiler is specifically selected to providesupport for parallelization directives such as the exemplary OpenMPstandard. The second compiler is utilized to build the executableprogram, that executable program providing for processing by multiplethreads of operation during its execution. The organization, syntax, andstyle of the components of the intermediate program and theparallelization directives which are generated by the first stage ofprocessing are constrained and designed so as to be compatible and in aform suitable for processing by the second stage (standard) compiler.

The method(s) and approach of the present invention have the potentialor opportunity to provide the following several specific improvementsand advantages over the above discussed approaches of the prior art:

-   -   1) achieving parallelism for a program written in Cobol without        requiring the availability of a compiler that provides both        support for parallelism and support for Cobol as an input        language;    -   2) achieving better performance than would be achieved by        developing a singular new compiler designed specifically for the        purpose of supporting parallelism (through multiple threads)        during compilation of a Cobol source program; and    -   3) providing for continued benefit from improvements in compiler        technology, evolving hardware support and in general maintenance        of a high quality compiler with reduced maintenance costs and        less initial investment in compiler development.

The first improvement is achieved through use of the two-step (or twophase, or two stage) approach of the present invention described brieflyabove. That is, as described with reference to one illustratedembodiment, translating a Cobol source program into C, and thencompiling the C program with a second compiler to produce an executableprogram, the two-step process providing throughout such processprovisions for both describing parallelism and for building an outputexecutable program which includes parallelism during execution. Thiswill be described in more detail later herein.

The second improvement is also provided, as part of the two-stepapproach, by choosing or selecting as the second stage compiler thatproduces an executable program that is highly performant. That is, sincethe second compiler is the program that actually builds an executableprogram, it is very important, in terms of achieving best performance,to choose or select as a second compiler, a compiler that generates asan output, a well optimized, highly performant executable program. This“best” choice of compiler is likely to result in selecting a compilerfrom a company that is a manufacturer or designer of the processoritself, (such as Intel Corporation), or from a large company such asMicrosoft Corporation with many resources in terms of personnel andexpertise, and with good relations with the hardware designers. It ispossible also that an Open Source compiler such as GNU C/C++ would be agood choice because of the large amount of effort expended by manypeople to make it a good compiler. The point is that using a very goodcompiler such as that from Intel Corporation in a second stage ofcompilation results in producing an executable program that is likely toperform better on that company's hardware than using a methodology basedupon development of a single stage compiler.

With regards to the third improvement described above, these maintenancebenefits are achieved by utilizing, in the manner just discussed, a“best choice” or “major” compiler as the second compiler. Further, whennew hardware evolves, or new compilation or programming efficiencies aredeveloped, the first compiler can be adapted (if necessary) ormaintained with very minimal support because it is translating a programinto a standard language (such as “C”) and therefore changes intechnology which are developed are likely to be provided in thatstandard language, or accommodated by the second compiler. Thus, onlysmall changes to the first compiler are likely to be needed to supportadvancement; the larger part of the changes most likely to be providedby the “standard” second compiler.

Considering the above again but in more detail, with reference to anillustrated embodiment of the invention, parallelism is achieved by amethod that implements a two phase approach. The first phase is atranslation performed by a special compiler that operates to translate aCobol program to an intermediate computer program which is in a secondcomputer language. The translation includes the operations of theordering of the Cobol statements and the translation of the Cobolstatements into a form specifically designed for parallelism which arerecognizable by a selected or chosen second compiler.

The second phase is a compilation step, performed by the chosen secondcompiler, for building an executable program utilizing the intermediatecomputer program in the second language (i.e. generated from the firstphase) as input to the second compiler. The second compiler is utilizedto build the actual output executable program or object file. The secondcompiler is a carefully selected already existing (standard) compilerthat supports parallelization (such as OpenMP architecture). Thespecialized first compiler is designed specifically for the purpose ofpreparing input in a manner acceptable to the selected second compiler,with the input to the second compiler including description of theprogram including variables and program flow, description ofparallelism, with the program variables and program flow being in formwhich accommodates the description of parallelism.

This approach provides for parallelism without requiring developing orprocuring a compiler designed with both direct OpenMP architecturalsupport and direct support for Cobol as an input programming language.Moreover, this approach overcomes the need for developing such acompiler when a compiler which supports OpenMP architecture is notavailable in the marketplace for a Cobol source program, and, even ifsuch a compiler were to be available, this approach provides forimprovements such as reduced maintenance, improved performance, andbetter support for outside tools such as debug tools developed by othercompanies for a common language such as C/C++.

It will be appreciated that it is not just a lack of the availability ofany general compiler for achieving parallelism in Cobol that enables animprovement over the prior art. The invention also satisfies a need forperformance, a desire for broad machine support, good debug tools,measurement and analysis tools and other similar advantages which areoffered by using commercial vendors' tools with these features providedin best form on “important” modern languages, such as, C/C++ andFortran. With application of the method of present invention, some orall of these advantages are provided for a program written in Cobolwhile also providing for parallelization utilizing multiple threads ofprocessing during execution of the resulting executable program.

In order to further appreciate how the method of the present inventiondiffers from the typical prior art approach, it is helpful to compare ingreater detail, the method of the present invention with the typicalapproach of providing a parallelizing Cobol compiler through developmentof a single pass Cobol compiler which directly supports the OpenMParchitecture. (While to the inventor's knowledge, no such single passcompiler exists, this approach would be typical of developmentapproaches known in the prior art) This prior art approach, withoutrequiring a very major investment, would likely not achieve the quality,robustness, and broad base of tool support provided by the utilizationof a major commercial compiler as a second step in the processing of theCobol program. In fact, without an intimate knowledge of the hardwareand software, it would be likely that even with considerable investmentboth the performance and the features provided by a single pass compilerwould not be as good. Further, support for ever evolvinghardware/software platforms and features would require continuedmaintenance, whereas with the approach and method of the presentinvention, as improvements are made to the selected commercial compiler,these improvements will be naturally provided without any or withminimal added development on the first compiler.

Because of close and intimate knowledge of the workings of their owncompany's hardware and software, and because of partnerships with othermajor commercial vendors, companies such as Microsoft Corporation orIntel Corporation can develop compilers which provide for betteroptimization and more features than what is likely to be provided byindividual developers or developers in smaller or less connectedcompanies. For example, utilizing a major compiler such as a C/C++compiler from Intel Corporation as a second compiler provides thebenefits of good optimization and continued improvement as hardwarechanges and evolves. According to the teachings of the presentinvention, using the special compiler in a first phase to perform aspecial translation of Cobol as for example which includes capabilityfor expressing and describing parallelism within a Cobol programprovides for that parallelism in the first phase, and relies on use ofan already existing compiler from a major vendor in a second phase andtakes advantage of features of both compilers.

The OpenMP standard for parallel processing in C/C++ or Fortran programsalready provides directives specifically designed to accommodate thelanguages of C/C++ and Fortran. Thus, the OpenMP standard provides anopportunity for accomplishing parallelization which is an alternative tobuilding a compiler with completely automatic parallelization, suchapproach having been shown in the past to be a difficult task for acompiler. Other exemplary prior art approaches for describing orproviding parallelization include “MPI” which is a Message PassingInterface”, and “PThreads” which IEEE POSIX standard (Institute ofElectrical and Electronic Engineers, and Portable Operating SystemInterface).

The OpenMP standard itself can be found on the OpenMP.org website withthe latest version at this being Version 3.0 dated May 2008. Asdiscussed, OpenMP architecture provides a way for a runtime entity toperform processing using multiple threads, with “threads” being anentity that is able to independently execute a stream of computerinstructions. Multiple threads may interact, but can also runindependently. OpenMP architecture provides for a single set of sourcefiles that can be run as a single thread or for enabling multiplethreads of operation. Multiple threads may be executed on a singleprocessor, or on a machine with multiple processors and/or multiple“cores”. Multiple threads typically work concurrently to accomplish thework of executing a parallel program.

Also, OpenMP architecture provides directives to create teams of threadsfor parallel execution, to specify how to share work among the threads,to declare and describe both shared and private variables, and also toprovide means for synchronization and communication between the threads.OpenMP architecture provides these directives for programs written inthe C/C++ and Fortran computer programming languages. According to theteachings of the present invention, and in order to take advantage ofutilizing the OpenMP architecture approach and the OpenMP library tocreate and manage parallel processing in a Cobol program, the Cobolprogram is analyzed and “translated” by a special compiler with specificregard to accommodating the generation of a parallel executable programby a second compiler. That is, the translation performed by the specialcompiler includes an analysis of the Cobol program and generation ofintermediate program code that is specifically designed to be in a formrecognizable by the second compiler. A general straight-forwardtranslation of Cobol to C as typically performed in the prior art willnot provide for C/C++(or Fortran) in a form that will allow or enableparallelization. Further, the straight-forward approach of performing asimple translation also does not provide for an intermediate program forwhich parallelization directives could be inserted as for example, byhand (e.g. by the programmer).

It will be noted that OpenMP architecture provides a fairly small numberof directives for describing parallelization in a C/C++ program. A“Parallel Construct” defines a region of code in which parallelizationis allowed. “Work Sharing Constructs” provide a mechanism for describingparallelization of loops, single threading of specific sections within aregion of parallelized code, and splitting of work into “Sections”.OpenMP architecture also provides synchronization constructs such as“Barriers”, “Critical” areas, “Atomic” constructs, “Locks” and defininga “Master” thread. The Cobol to C translator developed and utilizedaccording to the teachings of the present invention provides fordescribing multiple threads in a manner which can be applied to a Cobolprogram, with the translator transforming the Cobol program to expressparallelization in a related C/C++ (or Fortran) transformed program,with this transformed program being written to an intermediate programfile for further compilation by a selected second compiler.

Considering as an example, the Cobol programming language provides astatement called a “PERFORM” statement which describes repeatedexecution (looping) of a specified section of code. In Cobol, a PERFORMstatement may describe looping of code that is described in a differentarea of the program (not immediately following the PERFORM statement).The PERFORM statement works in a manner somewhat similar to that ofinvoking a subroutine or macro in the C language. The PERFORM statementin a simple translation might be translated to a sequence of code thatincrements a loop variable and tests for conclusion or termination ofthe loop with an IF statement, with the work of the PERFORM block beinghandled as a subroutine call. This translation approach, in general,does not however provide for C/C++ code which allows forparallelization.

As another example, A COBOL PERFORM statement might be translated, inthe manner of the prior art (e.g. the OpenCobol.org compiler), into a C“WHILE” statement. This approach however produces C code which is notsupported by OpenMP architecture for parallelization because, forexample, the “WHILE” construct is not supported by OpenMP forparallelization). Therefore, according to the teachings of the presentinvention, the first stage of translation is carried out in a mannerwith the specific intent of producing intermediate program code that isin an order, style, organization and supportive of compilation by achosen or selected second compiler, that produces parallelization in theoutput executable program.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The subject matter of the invention is particularly pointed out anddistinctly claimed in the concluding portion of the specification. Theinvention, however, both as to organization and method of operation, maybetter be understood by reference to the following description taken inconjunction with the subjoined claims and the accompanying drawings inwhich:

FIG. 1 illustrates a compilation methodology of the prior art in which aCobol program is compiled without support for parallelization, and by asingle phase approach using a single compiler;

FIG. 2 illustrates a compilation methodology of the prior art in which aCobol program is compiled using a typical straight-forward translationof a Cobol source program into a second language illustrated as the “C”language, followed by a compilation by a second compiler illustrated asthe GNU C compiler, an industry standard compiler;

FIG. 3 provides illustration of the compilation of a Cobol programaccording to the teachings of the present invention using a two stagecompilation process which includes as the first stage, use of aspecialized compiler which prepares an intermediate program thatincludes provisions for parallelization directives, an intermediateprogram style and ordering that supports parallelization;

FIG. 4 illustrates a compilation flow depicting a specialized compilerthat analyzes program constructs within an input Cobol program andproduces suggested parallelization directives and OpenMP pragmas, andfurther optionally provides a parallelization report describing to aprogrammer suggested regions of parallelization identified by thespecial compiler, and further, optionally, provides a description ofproblems with certain Cobol constructs that prevent parallelization ofspecific regions of Cobol program code;

FIG. 5 illustrates a very simple Cobol program for demonstratingconversion of a Cobol program to a C program according to the prior artby a compiler from Cobol-IT.org which is based upon the OpenCobol.orgCobol to C compiler;

FIG. 6 illustrates the output produced by the Cobol-IT.org Cobol to Ctranslator when given as input the very simple Cobol program of FIG. 5;

FIG. 7 illustrates the same very simple Cobol program of FIG. 5 withparallelization directives added to describe one region ofparallelization;

FIG. 8 illustrates the output from a special compiler implementing asimple translation of Cobol to C according to the teachings of thepresent invention for the very simple Cobol program of FIG. 7;

FIGS. 9A, 9B, and 9C together illustrate a Cobol source programimplementing matrix calculations of intrinsic trigonometric functionssine and cosine (for brevity, these three FIGS. 9A, 9B, and 9C will bereferred to herein as FIG. 9);

FIGS. 10A, 10B, and 10C together (for brevity, these three FIGS. 10A,10B, and 10C will be referred to herein as FIG. 10) illustrate outputfrom a special compiler translating, according to the teachings of thepresent invention, the Cobol source program of FIGS. 9A, 9B, and 9C intoa “C” program suitable for insertion of parallelization directives (withOpenMP pragmas inserted in this illustration);

FIG. 11 provides a comparison of execution times for execution of theCobol program of FIG. 9 in comparison to the execution time of the sameCobol program with provision for parallelism provided according to theteachings of the present invention;

FIG. 12 illustrates computer system hardware suitable for utilization inperforming the steps of the method of the present invention and also asa platform for executing a program using multiple threads of processingin the manner described for running the executable program produced bythe steps of the method of the present invention.

FIG. 13 illustrates, in an exemplary flow chart illustrating at leastone embodiment of the present invention, a flow wherein a user selectsregions for parallelization from one or more suggested regions ofparallelization generated by a first compiler, and after suchselection(s) generates a multi-threaded executable with a secondcompiler;

FIG. 14 illustrates, in an exemplary system of one embodiment of thepresent invention, wherein a user selects regions for parallelization byinserting parallelization directives into “C” code generated by thefirst special compiler, these directives defining regions ofparallelization, and after these insertions have been made, generates amulti-threaded executable with a second compiler;

FIG. 15 illustrates, in an exemplary system in another embodiment of thepresent invention, wherein a user defines regions for parallelization byinserting parallelization directives into an original Cobol source codeand a first special compiler then generates a C program which creates Ccode in a form suitable for parallelization and in which parallelizationdirectives included that are suitable for generating a multi-threadedexecutable program by a second compiler; and,

FIG. 16 illustrates in another exemplary system illustrative of anembodiment of the present invention, wherein a parallel analysis toolwith optional guidance by a programmer or user is used to analyze theintermediate C program generated by the first compiler/translator, theanalysis providing guidance for either the tool or the user to insertparallelization directives, e.g. in the form of OpenMP pragmas, into theintermediate C program.

DETAILED DESCRIPTION OF THE INVENTION Overview

The present invention provides a method for compilation of an originalCobol program, that method providing for building an executable programwith support for multiple threads of processing during execution orrunning of the executable program. Multiple threads of operation providein some cases for significantly improved performance in the execution ofthe Cobol program in comparison to using a single thread of execution.The improvements achieved can potentially provide for a performanceimprovement approaching 2×, 3× or more as two, three or more threads ofprocessing are applied, in comparison to the performance achieved by theuse of a single thread.

As described herein, in an illustrated embodiment of the presentinvention with reference to FIGS. 14 and 15, a special purpose compileris utilized to read an original Cobol source program from a computerfile system into an addressable memory of a computer system. Thevariable declarations and the structure of the Cobol program areanalyzed in memory and as a result of the analysis specific regions ofthe Cobol program are identified as having potential for application ofmultiple threads to the processing in the manner of the original Cobolsource program. Regions for potential parallelization may also beidentified based upon user input, or embedded content within the Cobolsource program itself.

The special purpose compiler provides several functions, the first ofwhich is to translate the Cobol source program into a substantiallyequivalent program expressed in a second computer language, with thetranslated output written to a file on the computer system. In thisillustrated embodiment, the second language is either C/C++ or Fortran.The special purpose compiler further provides analysis of the inputoriginal Cobol program and utilizes the results of analyzing thestructure, program order, variable types and other such informationbased on analysis of the Cobol source program to define regions ofparallelization or regions for potential parallelization. Again,selection and determination of these regions may be further based uponboth programmer input to help guide the compiler in determining orlocating the potential/possible or the best regions for parallelization.

As part of the translation process, the special purpose compilerorganizes and arranges the program statements in the second language inan order and in a form suitable for describing regions of potentiallyparallelizable code to a second compiler; the second compiler being acompiler supporting generation of an executable program which enablesparallelism through the use of multiple threads of execution. In thisillustrated embodiment, the intermediate program is written to a fileoperatively coupled to or included within the computer system, and thenthe intermediate program given to the second compiler program forprocessing. The parallelization directives may for this illustratedembodiment be in the form of the OpenMP standard. The second compilerreads the intermediate program file, processes it in the memory of thecomputer system (the same computer system, or a different one), andbuilds an executable program which is written as output into anothercomputer file, that file being in a special format and marked asintended for execution. The compiler may optionally produce either an“object” file, or an executable file, the object file being a file whichcan be combined with other objects to build an executable program. Theexecutable program can be specified to be prepared for execution on thesame computer on which it is compiled or on another computer, or ondifferent model of a computer.

The method and system of the invention provides for significantpotential improvement in the execution time performance of a Cobolprogram by enabling parallel processing using multiple threads ofprocessing during execution of the Cobol program.

The method and system of the invention provides further advantage inthat development of a compiler with direct support for Cobol for exampleis not required, thus reducing development time and cost, debug time andcost, maintenance time and cost, and significantly increasing potentialfor reliability of the parallelism constructs in the generated programcode.

The method and system of the invention also optionally providespotential for use of existing debug, performance measurement, andprogram analysis tools which already exist for the already supportedform or language, that supported form typically being C/C++, or Fortran,and also typically with the OpenMP approach.

It is a further advantage of the method and system of the invention toprovide for Cobol language support, for example, in a generatedexecutable program for debug and application of debug tools and debugenvironments in the manner currently provided for C/C++ and/or Fortran.

It is a further advantage of the method and system of the invention toprovide measurement tools for analyzing performance as an aid to aprogrammer in determining areas best suited for parallelization.

It is a further optional advantage of the method and system of theinvention to provide as part of the overall Cobol compilation processfor inclusion of code in the output executable program which would aidin verifying correctness of any multi-threaded execution of a Cobolprogram.

Translation of a source program described in one computer language to asecond source program described in a second source language is notunique or novel. Indeed there are a number of programs that provide forsome manner of Cobol to C translation. However, simple translation inthe manner described in the prior art does not provide support forparallelization constructs, and further, as discussed above, support forparallelization cannot be provided using the output from a simpletranslation. Consideration of specific constructs, proper choice ofvariable types, specific structure and ordering of the code, and othersuch requirements are necessary to enable parallelism. Thus, in view ofthe above, it is seen that it is not currently feasible for Cobolprograms of any significant complexity to use a simple Cobol to Ctranslation as it exists in the prior art to achieve parallelism in anoutput executable program. The translation techniques of the prior artare unable to translate Cobol to C in a manner that allows use of OpenMParchitectural or parallelization constructs. Further, the prior artmanner of translation does not lend itself to the introduction ofparallelization constructs such as those used in OpenMP architecture,even if those constructs were to be added by hand by a programmer afterto the intermediate file after the translation was made.

In one illustrated embodiment, the present invention provides fortranslation by a first compiler of an original Cobol source program toan intermediate source program in C/C++ in a specialized manner designedto provide for including for specification, in the manner of OpenMParchitecture, of parallelization constructs to be then applied bypassing the intermediate source program through a second compiler; thesecond compiler typically being available from a major vendor, andproducing an output executable program that provides for multiplethreads of execution, with such multiple threads providing forobservably improved performance during subsequent execution of theoutput executable program wherein the improvement in performance isachieved during execution of instructions within regions of the programdesignated as supporting multiple threads and the improvement in eachregion being related to the number of threads utilized during itsexecution.

A two stage approach of compiling a Cobol program utilizing a known(typically commercial) compiler (second compiler) means that the inputformat recognized by the known compiler is specified by the manufacturerof that compiler. That is, the input source program to the “known”compiler is provided in a specific form in order to be properlyprocessed by the known compiler. More specifically, according to anillustrated embodiment of the present invention, the input to the secondcompiler is a C/C++ program, properly formed for processing by thesecond compiler. In order for parallelization to be enabled, the sourceto that second compilation further provides for the specification ofparallelization constructs in the manner specified by the manufacturerof the known second compiler. And also, the program code is generatedsuch that the parallelization constructs can be successfully applied toenable multiple threads of processing in the output executable program.

For purposes of further illustration of the above, let us assume thatthe Intel C/C++ compiler is chosen as a “known” second compiler, andthat it is to be run with provision in the input source files for OpenMP“pragmas”. These “pragmas” are typically processed when enabled by acompiler option. In an illustrated embodiment of the present invention,an original Cobol source program is processed (translated) by a firstcompiler program according to the teachings of the present invention,and the output of that processing is an intermediate source program inthe C/C++ language. This C/C++ intermediate source program is thenprocessed by the Intel C/C++ compiler to produce an output executable orobject file. The translation by the first compiler program includesprovision for generating OpenMP pragmas in a proper form and includesthem in the intermediate source program. The intermediate source programis then submitted for processing by the Intel C/C++ (ICC) compiler, forexample, to produce an executable or object file that enablesparallelism through the use of multiple threads during programexecution.

An important factor in realizing the potential for success using the twostage translation/compilation approach of the present invention isdetermining and expressing precisely the details of style, ordering, andselection of constructs to be utilized in the expression of the Cobolsource program in the intermediate (second) form in order to enableapplication of parallelization constructs by the second compiler (e.g.example, Intel C/C++ compiler). It is essential that there iscorrectness in the translation of the original Cobol source program intoan intermediate program having the same relative functionality as theoriginal Cobol source program, but expressed or defined in a secondlanguage (for example, C/C++), and that the intermediate form generatedby the first compiler enables parallelization in a manner that issupported by the second compiler (e.g. Intel ICC compiler). Achievingthis requires consideration of a broad number of factors in determiningthe specifics of the translation process. These factors includeutilization of one or more of the following rules or guidelines:

1) providing a method of translating variable names as declared in theoriginal Cobol source program into variable names that meet therequirements of the second language; (for example, changing “-” hyphensto “_” underscores because Cobol allows hyphens in names and C/C++ doesnot)

2) providing a method of translating variable names as declared in theoriginal Cobol source program so as to preserve recognition by a humanwhen those names are observed after the first translation process; (forexample, translating “SAMS-CASH-VALUE” to “SAMS_CASH_VALUE” rather thaninto a “computer generated” name which is less recognizable by a humansuch as “X_(—)126”)

3) providing allowance for translated variable names which “collide”meaning that alternative naming is to be provided to prevent twovariable names in the original Cobol source program from beingtranslated into the same variable name in the second language (C/C++);

4) providing for “Cobol like” parallelization directives such as “OMPPERFORM” (for a Cobol “PERFORM” statement) translated into C/C++OMPpragmas such as “#pragma omp parallel for” (for a C/C++“for” statement);

5) providing for declaration of variables in a manner so that thevariables can be instantiated in memory with proper scope so that duringexecution, processing can be performed by multiple threads withoutinterference between memory references from different threads to thesame variables; and,

6) providing for locating the declaration of some variables within thestructure of the intermediate source program so as to provide fordeclaration of the variables within the limited scope of a parallelizedregion of the code, thus providing isolation of variable data betweenmultiple threads.

The techniques of providing for the translation of a Cobol sourceprogram in a manner that enables parallelization to be describedutilizing directives such as those provided in OpenMP architecture,through an intermediate program language such as C/C++ or Fortran isfurther illustrated with reference to examples of the current state ofthe art described in contrast to the teachings of the present invention.

By way of background, in the prior art, utilizing a single stagecompiler without support for parallelization, a Cobol source filedescribing a Cobol program is typically read in during a first pass ofthe single stage compiler, and at that time, internal tables are builtto describe within the first compiler, the Cobol variables, the Cobolprogram statements, and optionally the comments within the Cobol sourceprogram. These internal tables are then examined during subsequentpasses of the first compiler to determine and organize the desiredfunctionality, the desired Cobol variables and their data types andother such information as is standard in a computer program compiler.Once these internal tables are completed, the functionality and flow ofthe Cobol source program can be understood and analyzed further by thecompiler.

Typically, in a standard way, the compiler generates an executableprogram file that includes machine code or assembly languageinstructions which implement the desired Cobol program functionality,including initialization and preparation of the data structures.Providing support for many different hardware platforms and operatingsystem software platforms however may require significant developmentand verification when this approach is used.

It is noted that in the OpenMP standard a region of code is definedwithin the standard as “all code encountered during a specific instanceof the execution of a given OpenMP construct or library routine. Aregion includes any code in called routines, as well as any implicitcode introduced by the OpenMP implementation”.

DISCUSSION OF FIGURES

FIG. 1 illustrates the flow of a typical prior art method providing forcompilation of a source program to produce an executable program, orobject file. In FIG. 1, a Cobol Source Program 101 is typicallycontained in either a single file, or several files which are storedwithin the files of a computer system. A Cobol Compiler Program 102 suchas a Cobol compiler from the MicroFocus company is used to read in theCobol source program from the file or files containing the Cobol sourceprogram. The Cobol compiler program compiles the Cobol source programand produces, as output, an Executable Program 103 typically stored on afile of the computer system. As is well known in the art, compilers alsoproduce files in other formats such as “object” files which can later beused to build an executable file. The term “executable” is meant to beinterpreted broadly in a general manner meaning any output form whichdescribes a program such that it is ready, or can be easily be madeready for execution or combined with other files so as to be ready forexecution or running. The term “executable” thus encompasses the outputof a compiler in a form ready for execution, “linking”, “dynamiclinking”, or other similar terms used in the computer art. That is, theterm can be used to describe or refer to a program that has beencompiled to produce “executable” instructions. The executableinstructions may also take the form of “byte code”.

Another approach of the prior art for providing compilation of a Cobolprogram is illustrated in FIG. 2. This prior art method provides forgeneration of an executable program using two distinct phases ofprocessing. The first phase provides for compilation by a first compilerto translate a program from a first language into a second language,(instead of outputting of machine code or assembly language). Then, thecomputer program in the second language is fed into a second compiler,which supports (understands) the second language, to produce an outputexecutable. That is, a first compiler produces a second computer programin a second language instead of an executable, with the second computerprogram describing the functionality of the Cobol program in thatdifferent or second computer programming language. This second languageis then compiled by a second compiler to produce in a standard way, anoutput executable. This output executable from the second compiler willperform functionally as described by the programmer in the originalCobol source program, even if the second compiler did not providesupport for input in the first language of Cobol. This approach totranslation of a Cobol source file to a second source file, the secondsource file being in an intermediate language, followed by compilationof that second source file with a second compiler to produce an outputexecutable, has been described and implemented in an open sourcecompiler from the organization OpenCobol.org. OpenCobol.org offers acompiler that translates Cobol to C (or C++). The OpenCobol compiler isused to read in a Cobol source program and perform a translation to Cwhich is written to an intermediate output file. The intermediate outputfile is then provided as input to a second compiler which is typically astandard C compiler such as GCC (GNU Compiler). The second compilerreads and compiles the C language description in the intermediate fileand generates either an output executable, or an object file that can beused to build an executable. The output executable performs thefunctions described in the original Cobol source program. The approachused by OpenCobol.org in their OpenCobol compiler is described on theOpenCobol.org website as follows:

-   -   “Open COBOL is an open-source COBOL compiler. Open COBOL        implements a substantial part of the COBOL 85 and COBOL 2002        standards, as well as many extensions of the existent COBOL        compilers.    -   Open COBOL translates COBOL into C and compiles the translated        code using the native C compiler. You can build your COBOL        programs on various platforms, including Unix/Linux, Mac OS X,        and Microsoft Windows.”

FIG. 2 illustrates the compilation process intended for use by theapproach of the OpenCobol.org compiler as it is offered to the publictoday. The same approach is also provided by another similar compilerfrom another company called “Cobol-IT” (a French company with offices inParis) which has built a compiler based upon a fork from theOpenCobol.org compiler. As shown in FIG. 2, a Cobol Source Program 101is processed by a simple translating program 210 such as theOpenCobol.org translator 211 or the Cobol-IT Translator 212. The simpletranslator 210 translates Cobol in a straight-forward manner into anIntermediate Program 220 written to a file and described in a secondlanguage such as C/C++(or Fortran) a program containing functionalityequivalent (or substantially equivalent) to the Cobol source program.The intermediate program file is then processed in a second phase by asecond compiler such as the GNU C/C++ compiler 230. The GNU compilerthen performs a compilation of the intermediate program and produces anExecutable program 240 (or “object” file as discussed previously).

The standard language translation approach as implemented byOpenCobol.org shown in FIG. 2 does not however provide any support forparallel programming, and in fact generates intermediate C code that isnot suited for the addition of parallel programming constructs ordirectives, even by hand, in the intermediate output.

In the translation approach of OpenCobol.org and computer languagetranslation approaches of the prior art, assumptions are made for easeof programming, and techniques of translation are chosen which expediteimplementation of the translator, and/or efficiency of the generatedcode. These approaches and assumptions typically result in a translatedoutput that is not suitable for the addition or inclusion ofparallelization constructs, even if attempted by hand, because thetranslated code, although functionally operative and correct, is notexpressed in a form to which parallelization constructs can be applied.The “problems” posed in trying to adapt a translator of the prior artfor an application enabling parallel programming are not readilyapparent until an attempt is made to use the intermediate code and totry to accomplish parallelization.

As a first example, it can be observed using the OpenCobol.org compilerthat variables in the original Cobol program are translated to variablenames which are unrelated to the original Cobol variable names. Forexample, Cobol variables “total-amount”, “final-value” and “balance” maybe translated to C variables such as “a_(—)5”, “a_(—)6” and “a_(—)7”respectively. This does not affect the functionality of the executableoutput, because the internal variable names used in describing anapplication program or any computer program in Cobol (or any otherlanguage) are typically invisible to the actual user of that applicationprogram. However, parallelization oftentimes requires detailed study andanalysis of the variables within a program, both during a first step ofdesigning and describing proposed parallelization, and also in debuggingan application in which parallelization may not be producing expectedresults. It is a significant improvement to provide variable names whichare readily understood by the programmer with reference to the originalCobol variable names rather than creating and utilizing “computergenerated” names which make little sense at first glance.

Continuing with a discussion of variables and variable names, the word“scope” is typically used as a general term describing the visibility oraccessibility to a variable in a program. For example, an index variablein a program loop may or may not be “visible” outside the code of theloop itself. In attempting parallelization, it is often important toanalyze a variable's scope, for example, when multiple threads mayeither share or make private certain specified variables when the codereferencing those variables is to be executed by multiple threads. Toolsfor analyzing variables by name are available, one example being a toolcalled “ThreadChecker” available from Intel Corporation.

As a second example, the Cobol language typically provides for variabletypes which exist statically in memory. That is, Cobol variables whichare visible only inside a subroutine are typically not created on entryto the subroutine and then released upon exit from the subroutine. Thissimplistic approach is both good and bad in that it may require morememory to “persist” or always keep static variables in memory, but lesstime is taken in creating and releasing variables on a memory stack.With modern hardware, memory stacks are often accommodated quiteefficiently with hardware support for a stack approach, so the benefitsor disadvantages of not utilizing a stack are not necessarilypredictable; it depends on the specifics of the program itself. Forparallelization, a stack approach may be preferable because variablesthat are used only within a parallelized region can be created asthreads are created and these variables are then automatically isolatedfrom each other (between threads). Standard translation of Cobol to Cas, in the manner of OpenCobol, does not provide for this alteration invariable scope and/or type.

As a third example, variables in Cobol which are independently named maybe translated into variables which are simply references to locations inmemory or an array in memory. For example, Cobol variables “X”, “Y”, and“Z” may be translated to references to array locations “ARRINT[122]”,“ARRINT [125]” and “ARRINT[321]”. This choice prevents a programmer fromchoosing parallelization which keeps “X” in static memory, for example,and which would put “Y” in private stacked memory because the Cprogramming language does not allow one location in an array to bedefined with a different memory management type than another location inthe same array.

A fourth example regards optimization typically done by standardcompilers to provide for more efficient (faster) execution. Optimizationby a compiler may combine the processing of several statements into onepiece of generated machine code. Optimization may also move code in andout of loops if the compiler/optimizer decides that is both beneficialand still correct. There are many types of optimization. For parallelismto succeed however, optimization cannot be applied across the boundariesdefined for parallelization. For example, initialization of a variablewhich is described inside a PERFORM block of Cobol code might be movedoutside the PERFORM block and done instead just prior to entering thePERFORM code, if the compiler determines that will still result incorrect operation. However, when “parallelized”, it might be arequirement for correct operation to retain initialization within everythread of execution utilized in parallelizing a PERFORM statement.Therefore, the translator should be prevented from making certainoptimizations which “cross” parallelization boundaries.

A fifth example is the choice of constructs chosen for use in thetranslation of Cobol source code to another language. For example, a“PERFORM VARYING” construct in Cobol might in the prior art betranslated “correctly” to C code which might implement the checking forcompletion of the loop using a C “WHILE” construct. However, althoughfunctionally correct, a C “WHILE” construct is not supported forparallelization by OpenMP. Another approach may be to break down aPERFORM statement into a more primitive faun in a second language andexpress the functionality of the PERFORM using simple compute statementsand IF statements. For example, a PERFORM n TIMES in Cobol could betranslated into a series of statements in the C/C++ language such as:

index = 0; LOOP:    IF( index < n ) {      process body of perform;     index = index + 1;      goto Loop;    } else . . . . . . proceedwith following code . . .Code in this form however does not enable parallelization using OpenMPbecause there is no explicit loop construct (i.e. the loop isimplemented using a “goto” statement rather than with a “for”statement).

Another more complex example is illustrated with the Cobol same “PERFORMn TIMES” construct. This construct causes looping of the code aspecified number (“n”) times. Outside the loop, and typically just priorto the loop, variables which vary with each pass through the loopingcode are initialized, and then within the loop, typically at thebeginning or end of the loop, these variables are modified. When aconstruct such as this is parallelized, the code for determining thevalue of a variable during each pass through the loop is required to bebased upon a variable which is related to the pass number for the loop.This may require that a variable be created by the translation programthat does not exist within the original Cobol source, and that createdvariable is used as the basis for determining the value of variables aspasses are made through the code by each of a plurality of threads.

Therefore, in order for parallelization to be successful a translationapproach is utilized which implements a COBOL “PERFORM n TIMES” usingthe C/C++ construct of a C/C++“FOR” loop.

Often, it may also be true that it is not until the details of proposedparallelization are analyzed by a programmer that it can be decidedprecisely which approach to translation will provide the most benefit interms of enabling parallelization. Therefore it is a further advantagein accomplishing parallelization if the programmer is provided withconstructs to “suggest” a proper method of translation. These“suggestions” would probably be implemented as new “pragmas” forinfluencing the translation process. Of course other methods ofproviding these guidelines or “suggestions” to the translation processwould be readily apparent to one skilled in the art.

FIG. 3 illustrates a method according to the teachings of the presentinvention that provides for the compilation of a Cobol Source Program101 combined with Parallelization Directives 320 being inserted into theCobol Source Program 101 in a programmer defined manner to form anAnnotated Cobol Source Program 330. The Cobol source program istypically stored on a file within a computer system, and the AnnotatedCobol Source can either be maintained as a separate file, or theannotation version can be made a part of the original Cobol Sourceprogram (for example, using a “pragma” approach). The Annotated CobolProgram 330 provides a complete description of the functionality of theCobol source program 101 and also further provides programmer providedinformation describing where and how the programmer wantsparallelization to be implemented. The Annotated Cobol Source Program330 is typically also stored on a file in the computer system. A SpecialTranslator Compiler 340 is directed to read the Annotated Cobol Sourceprogram 330, to analyze that program and the features of that program asdescribed above. The special compiler generates as its output a C/C++Program 350 which includes within it parallelization directives 351 todescribed the programmer suggested parallelization for the Cobol program101 in manner suited to the generated C/C++ program 350. Note also thatthe first compiler optionally produces an Error/Warning Report 355 whenthe compiler discovers after analysis that parallelization cannot beachieved.

The intermediate C/C++ program 350 is then given over for processing bya second compiler 370 such as the Intel C/C++ Compiler, which providesfor parallelization of programs using OpenMP. The Intel compiler thenproduces as its output, an Executable Program file 380 which is anexecutable that provides for multiple threads of processing when thatexecutable program is executed (run). As mentioned previously, theexecutable can also be in the form of an “object” file.

An alternative approach to achieving parallelization in anotherillustrated embodiment according to the teachings of the presentinvention is illustrated in FIG. 4. In this illustration,parallelization is achieved by having the first stage Special Compiler430 analyze a Cobol Source Program and “suggest” parallelizationregions, that is, regions where the special compiler suggestsparallelization might be achievable based upon analysis of the Cobolprogram flow. The special compiler produces a C/C++ intermediate Program440 which includes within it, suggested OpenMP pragmas definingpotential or suggested regions of parallelization within the C/C++program 440. The Special Compiler 430 also optionally produces a reportdescribing in more detail information related to each suggested regionof the Parallelization Report 450. As indicated in block 460, theprogrammer can then examine the C/C++ intermediate Program 440 and makethe selection of parallelization regions for processing by marking thatselection in a file 470. This file 470 is then processed in a normalmanner by the second compiler 370 to build an output executable 480 withparallelization. With this approach, the special first compiler servesas an aid to the programmer in looking for and identifying potentialregions for parallelization, the special compiler basing its suggestionson analysis of the Cobol program statements and variable declarations.

FIG. 5 illustrates a very simple Cobol program which will be used as anexample to illustrate the prior art approach of translation in contrastto performing the translation according to the teachings of the presentinvention. In FIG. 5, a Cobol program is shown which includesdeclaration of a two dimensional array called “Table-C” corresponding toreference lines 511-514. As indicated in reference line 520, the Cobolprogram performs a simple calculation of filling the array (table) witheach entry in the table being assigned to hold a number which is the sumof the two indexes 540 into that location in the array Table-C.

FIG. 6 illustrates a portion of a computer listing of an intermediate Cprogram produced by using the Cobol-IT compiler (prior art) to translatethe Cobol program of FIG. 5 into a C program (partially shown in FIG. 6in reference lines 601-624), the compiler being used to illustratetranslation typical of the prior art, is not suitable for use in thepresent invention. FIG. 6 provides only a key portion of the translatedprogram for discussion, that portion being the C code which actuallyperforms the work of filling the table with the sum of its indexes (i.e.shown in FIG. 6 reference lines 611-619). An example of the entireoutput program produced by the Cobol-IT compiler (prior art) is providedin Appendix A pages 1 through 8.

FIG. 7 illustrates a translation of the same Cobol program 500 into asecond C program 700, with that translation performed according to theteachings of the present invention. This translation 700 in FIG. 7 isshown in contrast to the translation 600 in FIG. 6 of the prior art, toillustrate in its simplest form some exemplary basic features of aSpecial Compiler/translator 430 that incorporates the teachings of thepresent invention.

In FIG. 6, it can be seen that the prior art compiler generates a“while” loop (i.e. shown in reference line 610). This while loop couldnot be parallelized because OpenMP does not support the “while”construct.

It can be seen also that an “IF” statement (i.e. shown in reference line620) is used to evaluate the looping variable for exit from the loop.This manner of loop control is also not supported by OpenMP.

It can also be observed that the variable names within the codedesignated as FIG. 6 reference line 630 are not related to the variablenames used in the Cobol program of FIG. 5. Further, some variables areprovided as pointer variables or intermediate pointer variables (i.e.shown in FIG. 6 reference line 640). These constructs are not easilymaintained in implementing parallelization using OpenMP.

It is also noted that the translation illustrated in FIG. 6 does notprovide a human predictable translation of variable names so thatparallelization directives which relate to variables specified by Cobolvariable names can be easily applied to the C/C++ code in the generatedcode.

FIG. 7 presents approximately the same Cobol program 700 (i.e. shown inreference lines 701-732) as presented in FIG. 5, further includingwithin the program exemplary parallelization directives 718 719 725 726in an exemplary style, as might be interpreted by a special compilerdesigned for translating Cobol to C with provision for parallelization.Line 18 (i.e. shown in reference 718) defines the beginning of a regionin which multiple threads are to be utilized; therefore the threads canbe created at this point in the program 700. Line 19 (i.e. shown inreference 719) defines the beginning of a loop that will utilize themultiple threads in doing the work described within the loop. Line 25(i.e. reference 725) defines the end of the multi-threaded loop, andline 26 (i.e. reference 726) defines the end of the parallelized region.The need for reference line 725 could be eliminated if the compiler isprogrammed to automatically find or detect the end of the loop basedupon analysis of the Cobol program structure, this being performed as afurther part of the special parallelization analysis.

FIG. 8 illustrates exemplary output of a special compiler fortranslating Cobol to C code with provision for parallelization. Theoutput is in the form of a C/C++ program (i.e. shown in FIG. 8 asreference lines 800-829). This program illustrates variable namestranslated into human readable variable names as illustrated inreference lines 802 to 811. The parallelization directives illustratedin FIG. 7 as reference lines 718, 719, 725 and 726 are translated intoOpenMP pragmas for the C/C++ language, in a format that will beinterpreted properly by the GCC or Intel C/C++ compilers. FIG. 8reference line 813 illustrates an OpenMP pragma defining the start of aparallel region. Line 814 illustrates an open brace that begins andcontains the parallel region, which is ended in reference line 821 witha closing brace. An OpenMP directive is presented in reference line 815which informs the second compiler that the following line contains aC/C++“FOR” loop in a form suitable for parallelization. It is noted thatthe parallelization generated by the first compiler is provided in aform that is acceptable to the second compiler. The translationtransforms the Cobol program flow into one that is acceptable forparallelization using OpenMP directives. If transformation cannot beachieved, an error report (as shown in FIG. 3 reference 355) mayoptionally be generated by the first compiler.

FIGS. 9A, 9B, 9C, (FIG. 9) FIGS. 10A, 10B, 10C, (FIG. 10) and FIG. 11together are used to illustrate the application of the teachings of thepresent invention to an exemplary Cobol source program 900(Matrix3P.cb1) whose sections are shown in FIG. 9A reference lines901-924; FIG. 9B reference lines 925-954 and FIG. 9C reference lines955-970. The illustration is used in showing an exemplary performancegain achieved through the application of one or more aspects of thepresent invention.

FIG. 9A illustrates the Cobol source program as including anIdentification Division 902, a Program-ID Section 903, a Data Division904, and a Working Storage Section 905 corresponding to reference lines906-924, the Working Storage section containing the declaration ofvariables and data storage used internal to the Cobol source program900. Three table type variables of section 905 are declared with names“TABLE-A” 911, “TABLE-B” 916, and “TABLE-C” 921. As indicated, the threetables are equal sized tables with 200 rows and 5000 positions each cellof the table containing a single floating point number. Two additionalvariables 906, 907 which are “BINARY” type variables are declared forpointing to entries within the tables, and a third “BINARY” typevariable 909 is declared which is used for looping through the programenough times to allow for an accurate execution time measurement.

FIGS. 9B and 9C together illustrate the Procedure Division 925 of thesame Cobol source program 900, and describes the processing to beperformed by the Cobol program 900 during its execution. FIG. 9Billustrates the initialization of data within the three tables (i.e.TABLE-A, TABLE-B and TABLE-C) contained in reference lines 933-938,941-946 and 949-954. FIG. 9C illustrates performing a trigonometric sinand cosine calculation in reference line 960 using the contents of twoof the tables A and B and putting the result into the third table C.FIG. 9C further illustrates the Cobol program source code in referenceline 965 for printing out (displaying) one exemplary value from theresult table which is TABLE-C 921.

FIGS. 10A, 10B, and 10C together are an illustration of exemplary outputfrom a special compiler, sometimes referred to as a “first compiler” inthis discussion, in which the Cobol program 900 shown in FIGS. 9A, 9B,and 9C is used as input. The special compiler is utilized to translatethe Cobol source program of FIG. 9 into a C program 1000 illustrated inFIG. 10 corresponding to

[FIG. 10A Reference lines 1001-1025;

FIG. 10B Reference lines 1026-1054; and,

FIG. 10C Reference lines 1055-1079;]

with the result that the C program is in a form suitable for successfulapplication of parallelization directives by a second compiler. FIG. 10Acorresponds to a C translation based upon the Cobol source code shown inFIG. 9A. FIG. 10B corresponds to a C translation based upon the Cobolsource code shown in FIG. 9B. FIG. 10C corresponds to a C translationbased upon the Cobol source code shown in FIG. 9C. The entire program,as exemplified in FIGS. 9A, 9B, and 9C, however is typically read as awhole into the first compiler, in order that the first compiler willhave available to it knowledge of the overall program such as variabledeclaration types, names and other such information as it is making atranslation of the input Cobol source program in its entirety into arelated C program with provision for parallelization.

In FIG. 10A, variable declaration statements in the C/C++ programminglanguage included in reference lines 1009-1913, 1015-1019, 1021-1025 areshown which relate to the Working Storage Section of the Cobol sourceprogram. Tables A, B, and C are translated from Cobol form to a C“STRUCT” which contains within it these three tables in the same memoryformat as would be defined by a normal single pass Cobol compiler (suchas MicroFocus Cobol compiler). The variable names are translated in ahuman predictable manner as in this example from a name such as“TABLE-A” in Cobol reference line 911 into “TABLE_TABLE_A” in “C”reference line 1009. In similar manner, a “BINARY” type variable inCobol is translated from “I-BUMP” reference line 906 into “I_BUMP” inthe “C” code reference line 1004. The “level” or “scope” of thevariables declared in the “C” code may be or are dependent on theparallelization directives in the original Cobol source program.

In FIGS. 10A, and 10B executable “C” program code of reference lines1026-1054, 1055-1079 is illustrated as being produced by translation ofthe Procedure Division of the original C program, in a manner supportiveof the application of parallelization directives, shown for exemplarypurposes as being translated into OpenMP style parallelization pragmas.

Within FIGS. 9B, and 9C inserted parallelization directives (referencelines 930 933 941 949 956) are shown illustrating Cobol parallelizationdirectives which are translated by the first compiler into relatedillustrative OpenMP parallelization directives (reference lines 10291033 1041 1049 1058 respectively) which are in the form of pragmas. Inthe manner and style of OpenMP for “C”, according to the teachings ofthe present invention, Cobol parallelization directives have beendefined which are translated by the first compiler into OpenMP pragmas,and the program code is further translated by a second compiler in amanner that supports the application of the OpenMP pragmas. Within FIG.9B, reference line 930 illustrates a Cobol parallelization directive,expressed in Cobol comment form (pragma) which is then translated in arelated way into an OpenMP pragma as shown in reference lines 1029-1030in FIG. 10B. In similar manner, reference lines 933-934, 941-942, and949-950 in FIG. 9B are translated in a related way into OpenMP pragmasas shown in reference lines 1033-1034, 1041-1042, and 1049-1050respectively in FIG. 10B.

It will be noted that the executable “C” code as shown in referencelines 1034, 1042, and 1050 in FIG. 10B are “C” “FOR” statementsexpressed in a form suitable for application of the preceding OpenMPPragma statements in reference lines 1033, 1041, and 1049 respectively.Note also that the paired braces (“{ . . . }”) surrounding the “C” codeof each “FOR” loop on reference lines 1034-1038, 1042-1046, and1050-1054 in FIG. 10B correspond to the regions of code defined by thecorresponding “PERFORM” and “END-PERFORM” statements in the originalCobol source code, to which the parallelization directives have beenapplied.

FIG. 11 reference lines 1101-1127 illustrate sample run times for theoriginal Cobol source program 900 shown in FIG. 9, in which thegenerated “C” code as in FIG. 10 uses two methods of compilation. Asshown, the first compilation designated in reference line 1102 ignoresthe OpenMP pragmas resulting in an executable with a single thread ofexecution. The second compilation 1103 utilizes OpenMP to enablegeneration of an executable which in this illustrative example usesthree threads. With one thread, the exemplary Cobol program is timedusing the “time” command in reference line 1107 and executes frombeginning line 1107 to end line 1110 in 26.04 seconds (i.e. shown inreference line 1112). With three threads, the exemplary Cobol program istimed with the “time” command in reference line 1118 and executes frombeginning line 1118 to end line 1121 in 10.68 seconds (i.e. shown inreference line 1123). This comparison illustrates an execution timeperformance improvement ratio of 2.43, with the improvement beingaccomplished by implementing one or more aspects of the teachings of thepresent invention in an illustrated embodiment of the present invention.

FIG. 12 is an illustration of a computer system 1200 which provideshardware facilities for implementing the teachings of the presentinvention. The computer system includes a Processor System 1210 whichincludes Central Processing Units or Central “cores” 1220 which performprocessing in a conventional manner. A computer system with a singleprocessing unit could also be used for implementing the two stages ofthe compilation methodology according to the present invention. As shownin FIG. 12, the computer system includes a Computer System Memory 1230,a Computer Input/Output System 1240 and a number of Computer systemFiles 1250. The original Cobol source program is typically stored withinthe Computer system's File system 1250, accessed through the Computersystem's Input/Output System 1240, and read into Computer System Memory1230 for analysis by a first compiler. Following analysis, anintermediate file is written to the file system 1250, and then accessedin similar manner by a second compiler represented as a second block toproduce an executable file which is written to the file system 1250. Auser may interact with the computer system and edit files through a UserInterface 1260 typically operatively coupled to the input/output systemof the computer system for the purpose of influencing the steps of themethodology to be followed such by specifying options for the first orsecond compiler. The executable program file is executed (or “nm”) onthis same computer system 1200, or moved to another computer system.Running the program with multiple threads, especially on a computersystem with multiple CPUs or cores 1220 typically provides significantperformance improvement over equivalent execution with only a singlethread. In many cases performance improvement can be achieved which isalmost directly related to the number of threads. For example, if onethread has performance of 1.0, then two threads might have performanceof 1.9, and three threads might perform at 2.7, for example. There areof course limits on the number of threads which can be productivelyapplied to most problems, as is well known in the art. Improvement inperformance which is a reduction in execution time is observable by auser through the user interface 1260 using job monitoring programs thatare well known in the art.

FIG. 13 illustrates processing a Cobol Source Program 1310 in anexemplary manner according to the teachings of the present inventionusing a first compiler which is a Special Compiler/translator program1320 which performs analysis of potential parallelism on the Cobolsource program. The first compiler 1320 generates as its output anintermediate computer program in a second programming language 1330which in this example is a C/C++ program; this program in the secondlanguage is uniquely related to the Cobol Source Program 1310 in that itdescribes a program providing functionality which is either identical orvery substantially related to the program described by the Cobol SourceProgram. This intermediate C/C++ Program (program in a second computerprogramming language) 1330 includes within it regions of the executablecode 1340 which have been identified by the first compiler as havingpotential for implementing parallelization. The parallelization may beeasily recognizable in some cases, or the parallelization potential maybe achievable only after the further tuning of the Cobol program, orpossibly only after editing the C/C++ program. The regions ofparallelization 1340 within the C/C++ code could include, for example,in the terms of the OpenMP standard, C/C++“FOR” loops that have beentranslated from “PERFORM” statements in the original Cobol source code.The regions might also be loops that have been identified, for example,by flow analysis of the original Cobol based upon analysis of “IF”statements, branching statements, conditional branching statements, andindexes upon which conditional branches are based.

A User 1350, typically a programmer, selects for inclusion (furtherprocessing) 1360 via (for example) a workstation or terminal device, oneor more of the regions of potential parallelization. The selection mightbe made by deleting (or commenting out) parallelization directives thatare not selected or selection might be made in many ways readilyapparent as could be easily determined by one skilled in the art ofprogramming.

After the selection has been completed, a C/C++ program file 1370, whichincludes the selected pragmas presented in a manner so that they will beprocessed, is applied as input to a standard compiler 1380 such as theGCC or Intel compiler 1380. This compiler 1380 includes the requisitesupport for generating an executable program 1395 that provides formultiple threads of processing within the executable code, achieving thegoal to improve performance of the program over the performance thatwhich would be achieved without parallelism (or without multiple threadsof processing). The various files of the overall compilation process arestored on a file storage device(s) such as a disk drive 1394, which areaccessed typically through a CPU I/O System 1392. The overall computersystem which includes memory, the I/O system, file storage space andother hardware can then be used to “run” or execute the resultingexecutable program. The executable program could also be moved toanother computer system for execution or processing. In order to gainsignificant benefit in performance, CPU hardware which includes multiplecores 1396 is best suited in performing the processing, althoughimprovement with multiple threads might even be possible running on amachine having a single processing unit.

FIG. 14 illustrates processing a Cobol Source Program 1310 in anotherillustrated system embodiment consistent with the teachings of thepresent invention. A first compiler 1420, which is another form of aSpecial Compiler/translator program, translates the Cobol source programinto a C/C++ Program 1430 (intermediate computer program in a secondcomputer programming language). The translation is performed by compiler1420 such that whenever possible, the Cobol program 1310 is translatedso that parallelization directives can be applied to the intermediatecomputer program. That is, the components of the C/C++ program 1430 areexpressed in a manner so that parallelization directives such as thosespecified by OpenMP can be applied. A User 1450 typically a programmerthen Inserts Parallelization Directives 1460 (OpenMP pragmas forexample) into the intermediate computer program which results in a C/C++Program 1470 that includes regions for parallelization identified bypragmas.

The C/C++ program 1570, which includes the pragmas, is then presented asinput to a standard compiler 1380 such as the GCC or Intel compiler1380. This compiler 1380 includes the requisite support for generatingan executable program 1395 that provides for multiple threads ofprocessing within the executable code, achieving the goal of improvingperformance of the program over that which would be achieved withoutparallelism (or without using multiple threads of processing).

The various files of the overall compilation process are stored on afile storage device(s) such as a disk drive 1594, which are accessedtypically through a CPU I/O System 1392. The overall computer systemwhich includes memory, the I/O system, file storage space and otherhardware can then be used to “run” or execute the executable program.The executable program could also be moved to another computer systemfor execution or processing. In order to gain significant benefit inperformance, CPU hardware which includes multiple cores 1396 is bestsuited in performing the processing, although improvement with multiplethreads might even be possible when run on a machine having a singleprocessing unit.

FIG. 15 illustrates, in an exemplary flow chart illustrating a furthersystem embodiment for implementing the teachings of the presentinvention, in which a user 1550 defines regions for parallelization byinserting parallelization directives 1560 into an original Cobol SourceProgram code 1310 and in which the system then generates a C program bya first special compiler 1520 which creates C code 1570 in a formsuitable for parallelization and including parallelization directiveswhich are suitable for generating a multi-threaded executable by asecond compiler 1380.

Considering FIG. 15 in greater detail, it is seen that a Cobol SourceProgram 1310 is annotated by a user 1550, typically a programmer, toform an Annotated Cobol Source Program 1530. The Annotated Cobol SourceProgram 1530 includes both the original Cobol Source Program code 1310,and designations of potential regions for parallelization within theCobol program 1560. This Annotated Cobol Source Program 1530 is thentranslated by a special first compiler 1520, which is another form of aspecial compiler/translator program, into a C/C++ program 1570(intermediate computer program in a second computer programminglanguage). The translation is performed so that in whatever regionsidentified as a potential region for parallelization, the annotatedCobol program 1530 is translated so that parallelization directives canbe applied to at least those related regions of the intermediatecomputer program. If analysis by the translator program 1520 determinedthat this was not possible, an error message could be issued by thetranslator program as described above.

Then, in the same manner as described in connection with FIGS. 13 and14, the intermediate C/C++ program 1570 including the defined regionsfor parallelization is run through the Intel or GCC C/C++ Compiler 1380producing a multithreaded 1595 program for execution on the computersystem that includes a CPU I/O System 1392, multiple cores forprocessing 1396 and the appropriate files stored on a disk subsystem1594.

The techniques described above for providing improvements inparallelization, and other techniques, which may be defined by thoseskilled in the art, are not necessarily all that is required to achieveany parallelization, but by combining a plurality of techniquesaccording to the teachings of the present invention improves thelikeliness of success, that is, the goal of achieving higherperformance.

As a further example of the above, the ordering of the programstatements in the second language is also important. Compilersoftentimes “move” or change the order of generated code to provide forefficiencies in execution or other reasons. When contemplatingparallelization, it is important that the generated code in the secondlanguage be divided and ordered in a predictable way so that the secondcompiler can apply parallelization without destroying or affecting theoverall functionality of the program. Some optimization can be done bythe first compiler, but overall program flow between Cobol “paragraphs”is best maintained for success in parallelization. That is, statementscan be combined or re-ordered when it makes no difference in theresulting functionality relative to any entry points into a procedure,but re-ordering should not be done across boundaries in the programwhich are subject to change when parallelization is being considered orimplemented.

Describing parallelization in a manner that makes the descriptionavailable to the second compiler also requires special techniques. Inthe prior art, parallelization is often described to a compiler usingwhat are called “pragmas” as previously indicated. Pragmas are“comments” that are optionally interpreted by the compiler which maydescribe constructs and information not generally provided in thestandard computer language. The OpenMP language is based upon the use ofpragmas, these pragmas providing for “normal” single thread compilationif the pragmas are ignored, and providing for parallelism ormulti-thread operation in the executable when they are considered by thecompiler. Some compilers may choose to ignore some pragmas whileproviding support for other pragmas.

In providing a two stage approach which supports parallelizationaccording to the teachings of the present invention, an improvementresults by providing for processing of the pragmas in the source filesof the first language (Cobol) as they are being translated into thesecond language. First, provision must be made for passing any commentsat all from the source files of the Cobol program to the intermediateform. Normally (or typically) comments are ignored by translationprograms. That is, comments are simply discarded meaning they are leftcompletely out of the translated code, or they might be maintained inbasically the same form as in the original source files. Forparallelization to be successful, it is an improvement to provide atleast some recognition and processing of comments in the original Cobolsource, especially those which can be recognized as being related toparallelization or those which are actual parallelization “pragmas”.

For example, pragmas may reference variable names, the variable namespossibly being altered as the translation is made from the firstlanguage to the second language. In the prior art, pragmas which aretypically “just” comments, might be ignored, discarded, or left inoriginal form. Providing improved support for parallelization howeversuggests that any variable names in the pragmas be translated intovariable names in the second language in the same manner as variablenames are translated in the normal source of the program. In otherwords, it is an improvement to have the first compiler actually“translate” comment statements (pragmas) in the same manner that thenormal program statements are translated.

It is also a further improvement to maintain the order of comments,especially those comments recognized as relating to parallelization,relative to the normal Cobol source statements. That is, for example, itis beneficial to maintain a comment statement that describes the nextline of the Cobol program as being a parallelizable construct such as apotential “FOR” loop (in the C language) in the same relative locationas in the translated intermediate fowl in order to provide thatparallelization description properly to the second compiler.

FIG. 16 is a Figure similar to that of FIG. 14. In this FIG. 16 anexemplary flow chart is presented illustrating a further systemembodiment for implementing the teachings of the present invention. Inthe flow of this system implementation, the intermediate C/C++ programis analyzed by a parallel analysis program 1651 such as “FasThread”(available from Nema Labs as discussed in the Background of theInvention). Thus, the system implementation makes available to a user1650 or programmer, a program or tool 165 lwhich can be used to assistthe user 1650 in determining where to insert parallelization directives1660, and/or what type of parallelization directives 1660 to insert. Theuser may assist the tool, or if the tool is good enough, or the programsimple enough, the tool may be used in achieving full automation of theparallelization annotation. In the system implementation of FIG. 16, theuser and tool together modify the Intermediate Program 1430 until thetool 1651 determines parallelization is achievable and when this processis complete, an Annotated Intermediate Program 1670 is produced that hasgood potential for successful parallelization.

Thus, while the principles of the invention have now been made clear anddescribed relative to a number of illustrative embodiments orimplementations, it will be immediately obvious to those skilled in theart the many modifications or adaptations which can be made withoutdeparting from those principles. While the invention has been shown anddescribed with reference to specific illustrated embodiments, it shouldbe understood by those skilled in the art that various changes in formand detail may be made such implementations without departing from thespirit and scope of the invention as defined by the following claims.

Having described the preferred embodiments of the invention, it will nowbecome apparent to one of skill in the arts that other embodiments orimplementations incorporating the teachings of the present invention maybe used. Accordingly, these embodiments should not be limited to thedisclosed embodiments or implementations but rather should be limitedonly by the spirit and scope of the following claims.

What is claimed is:
 1. A method for generating, on a computer system, amulti-threaded program executable from an original annotated sourceprogram stored as a single file or module in storage of the computersystem, the original annotated source program written primarily in Cobolprogramming language which is a high level programming language, themethod comprising the steps: A) reading from the storage of the computersystem the original annotated source program stored as a single file ormodule and performing a first compiling operation, by a special Coboltranslator/compiler, the original annotated source program includingboth a) original Cobol program statements, and, b) originalparallelization directives, each original parallelization directivebeing related to a specific one or more of the original Cobol programstatements, is the special Cobol translator/compiler generating asoutput, an intermediate directly related high level language computerprogram in a second high level computer programming language other thanCobol and, as part of the compiling operation, the special Coboltranslator/compiler translating both the original Cobol programstatements and original parallelization directives into translatedintermediate program statements and translated intermediateparallelization directives respectively in the same second high levelcomputer programming language, and both the translated statements anddirectives being arranged in the output directly related intermediatecomputer program in an order directly related to that as existingbetween: a) the original Cobol program statements included within theoriginal annotated source program, and, b) the original parallelizationdirectives included within the original annotated source program; and,B) performing a second compiling operation by a selected standard secondhigh level language compiler on the intermediate directly related highlevel language computer program produced in step A, the selected secondhigh level language compiler including functionally that providessupport for: a) compiling of programming statements in the second highlevel computer programming language, and further including support forb) application, during the compiling, of parallelization directivesmixed with the programming statements, and, C) generating themulti-threaded program executable as output from the second compilingoperation of step B.
 2. The method of claim 1 wherein the compiling ofthe intermediate directly related high level language computer programin Step B further includes the substeps of: a) associating each originalparallelization directive with one or more of the original Cobol sourceprogram statements; b) generating any intermediate program statementsrelated to original Cobol source program statements associated with anyof the original parallelization directives in a form that enablesapplication of the intermediate parallelization directives to theseintermediate program statements; and, c) generating each intermediateparallelization directive in a form for describing parallelization,within programs in the second computer programming language, as providedfor by the selected second high level language compiler.
 3. The methodof claim 1 wherein the intermediate parallelization directives generatedin Step A are pragmas supported by the selected second high levellanguage compiler.
 4. The method of claim 1 wherein step B furtherincludes the step of translating original Cobol variable declarationstatements which include original Cobol variables with original Cobolvariable names, from within the original annotated source program, intointermediate variable declaration statements, each intermediate variabledeclaration statement declaring and describing in the second high levelcomputer programming language one or more intermediate program variablesdesignated by intermediate variable names and types, each intermediatevariable name being predictably generated based upon the original Cobolvariable names, and including these intermediate variable declarationstatements in the generated intermediate directly related high levellanguage computer program.
 5. The method of claim 4 wherein theintermediate variable names generated by the first compiling are namesdirectly and predictably related to the original Cobol variable names inthe original annotated source program.
 6. The method of claim 5 whereinthe generation of the translated intermediate parallelization directivesfurther includes predictably translating any variable names referencedwithin any of the original parallelization directives in precisely thesame manner as the original Cobol variable names are predictablytranslated in generating the intermediate variable declarationstatements.
 7. The method of claim 1 wherein the compiling of theintermediate directly related high level language computer program bythe selected second compiler is further controlled by the computersystem such that the multi-threaded program executable includes withinthe executable information that enables debugging and analysis of theexecutable using variable names directly and predictably related to theoriginal Cobol variable names.
 8. The method of claim 1 wherein thereading and compiling of step A further includes a step of providingstandard code optimization, but with scope of the standard codeoptimization restricted so as to prevent optimization associated withmultiple Cobol program statements, so as to avoid optimization thatwould span more than one described region for parallelization defined inthe annotated original source program.
 9. The method of claim 1 secondhigh level computer programming language is selected from the set of C,C++, and Java.
 10. A system for generating a multi-threaded programexecutable from an original annotated source program, the originalannotated source program written primarily in Cobol programminglanguage, a high level programming language, the system comprising: A)storage apparatus accessible by a computer system for storing theoriginal annotated source program, an intermediate directly related highlevel language computer program, and the generated multi-threadedprogram executable; B) a first control program controlling the computersystem to perform a reading and a first compiling operation utilizing aspecial Cobol translator/compiler the original annotated source programbeing read from the storage of the computer system, the originalannotated source program including both a) original Cobol programstatements, and, b) original parallelization directives, each originalparallelization directive relating to a specific one or more of theoriginal Cobol program statements, the special Cobol translator/compilergenerating as output the intermediate directly related high levellanguage computer program in a second high level computer programminglanguage other than Cobol and storing that intermediate directly relatedhigh level language computer program into the storage apparatus, and, aspart of the compiling, the special Cobol translator/compiler translatingthe original Cobol program statements into translated intermediateprogram statements in the second high level computer programminglanguage, and further translating the original parallelizationdirectives to translated intermediate parallelization directives in thesame second high level computer programming language, the a) translatedintermediate program statements, and, the b) translated intermediateparallelization directives, together arranged in the output directlyrelated intermediate computer program in a manner that is directlyrelated to the relationship existing between the corresponding: a)original Cobol program statements within the original annotated sourceprogram, and, b) original parallelization directives within the originalannotated source program; and, C) a second control program controlprogram controlling the computer system to perform a reading and asecond compiling operation using a selected second high level languagecompiler, the selected second high level language compiler includingsupport for: a) compiling of programming statements in the second highlevel computer programming language, and further including support forb) application during the compiling of parallelization directives mixedwith these programming statements in a single input source file ormodule, the selected second high level language compiler using as inputfor compiling, as input source code, the intermediate directly relatedhigh level language computer program generated in step A; and,generating and storing, into the storage apparatus, the multi-threadedprogram executable as output from the compiling a second time by theselected second high level language compiler.
 11. A program productcomprising a non-transitory computer readable storage medium storinginstructions for generating, on a computer system, a multi-threadedprogram executable from an original annotated source program stored as asingle input source code file or module in storage of the computersystem, the original annotated source program written primarily in Cobolprogramming language, a high level programming language, the programproduct including instructions for performing the method comprising thesteps of: A) reading the original annotated source program contained inthe single input source code file or module from the storage of thecomputer system by a special Cobol translator/compiler, the originalannotated source program including both a) original Cobol programstatements, and, b) original parallelization directives, each originalparallelization directive relating to a specific one or more of theoriginal Cobol program statements, B) compiling the original annotatedsource program and generating as output, an intermediate directlyrelated high level language computer program in a second high levelcomputer programming language other than Cobol, and, during thecompiling, the special Cobol translator/compiler translating theoriginal Cobol program statements and the original parallelizationdirectives into translated intermediate program statements andtranslated intermediate parallelization directives respectively in thesecond high level computer programming language, the translatedintermediate program statements, and, translated intermediateparallelization directives being arranged together in the outputdirectly related intermediate computer program in a manner directlyrelated to the relationship existing between the corresponding: originalCobol program statements within the original annotated source program,and, original parallelization directives within the original annotatedsource program, and the intermediate directly related high levellanguage computer program produced in step B being structured so as tobe ready for compilation by a selected standard high level languagecompiler, the selected standard high level language compiler beingcapable of providing support for both a) compiling of programmingstatements in the second high level computer programming language, andb) application, during the compiling, of the parallelization directivesmixed with the programming statements in the single input source file ormodule, during compiling for generating the multi-threaded programexecutable.